ENTOMOLOGICAL NEWS. [April, 



These would be dislodged by an unsteady lateral motion of the tip of the 

 abdomen. The larva would sometimes ascend the burrow, especially 

 after a new excretral opening had been made, and seizing the lower end 

 of the chain pellets before they dropped to the bottom, thus eject them from 

 above the opening. But usually it would seize the chain by the upper 

 end, and draging it up to the opening eject it from beneath, the chain at 

 first protruding upward at an acute angle, but as the middle was reached, 

 it would balance and hence be very readily pushed out. The ejection of 

 the pellets in chains is made possible by the way the larva makes the 

 opening. When beginning to gnaw through to the outer surface the 

 opening is large and irregular ; but gradually narrows down to a small 

 aperture by the time the epidermis is reached, thus making it broadly 

 sub-conical, and admitting the head just far enough for the mandibles to 

 reach the surface. The larva certainly pulled out a great many more 

 chips than is necessary to simply round out the burrow. This must be 

 considered as a waste of food material for which there would be no ex- 

 cuse, unless it is done to make sure of reaching the rootstock before 

 winter, even at the risk of exhausting the food supply, in case the larva 

 was in a small cane. But, as the larva was seen feeding from the sides of 

 the burrow, it may be that, on reaching the rootstalk, it feeds at random. 



To determine the necessity of its reaching the rootstock it was placed 

 in a blackberry cane five feet high and left undisturbed. It burrowed 

 down to within three feet of the surface and then stopped working, no 

 more castings appearing. An examination July 10, 1899, revealed the fact 

 that the larva had died, leaving this point still in question. But the fact 

 that we received similar larvae from the twigs of apple and pear in such 

 position that the larva could not reach the roots, would indicate that they 

 may feed until ready to transform and then pupate, regardless of the 

 rootstock. 



On August 21, 1899, at Langsville, Ohio, Oberea larvae were found 

 working in the young canes of red raspberry, the great majority having 

 already burrowed down into the rootstock, thus limiting their food supply 

 and certainly necessitating their transformation in one year, for it is mani- 

 festly impossible for them to make their way from one cane to another. 



This difference in life history is certainly important, and suggests the 

 possibility that there are two species in question. 



Ordinarily the larva of the Hessian fly, Cecidomyia destructor, has the 

 effect of destroying the central shoot of the young wheat plants, but this 

 year an exception to this rule was noticed in a plot of wheat sown on 

 unfertilized ground on the Experiment Farm. In quite a number of in- 

 stances plants having a full grown larva back of the leaf sheath the central 

 shoot was in good condition. In some cases the larva was lodged securely 

 just behind the upper end of the sheath at the base of the leaf, while in 

 others it was half way, and in others close down to the roots. Those at 

 the upper end of the sheath having attained the flaxseed stage are quite 

 certain to develop adults. This difference in the effect of the insect could 



